Qubit 4 Fluorometer

Fast and sensitive quantification of DNA, RNA, and Protein

The Invitrogen Qubit 4 Fluorometer is the next generation of the popular benchtop fluorometer designed to accurately measure DNA, RNA, and protein quantity. The new Qubit 4 also easily measures RNA integrity and quality. The easy-to-use touch screen menus make it easy to select and run the assays you need, with results displayed in just a few seconds.

The latest version of the Qubit fluorometer has been re-engineered to run the Qubit RNA IQ (integrity & quality) assay. The concentration or quality of the target molecule in the sample is reported by a fluorescent dye that emits a signal only when bound to the target, which minimizes the effects of contaminants on the result.

Sensitive, accurate, affordable

The Qubit® 3.0 Fluorometer is the next generation of the popular benchtop fluorometer that accurately measures DNA, RNA, and protein using the highly sensitive Qubit® quantitation assays. The concentration of the target molecule in the sample is reported by a fluorescent dye that emits a signal only when bound to to the target, which minimizes the effects of contaminants—including degraded DNA or RNA—on the result. The easy-to-use touch screen menus make it easy to select and run the assays you need, with results displayed in just a few seconds

How the Qubit Fluorometer works

Single-sample measurements are easy

This user-friendly fluorometer delivers results using quick, simple assay procedures. The large, color touch screen allows you to easily navigate through the various options. Calculations and settings are automatically performed by the instrument (Figure 1). The Qubit 4 Fluorometer will save the data for up to 1,000 samples, and you can transfer data using the USB cable or USB drive. In addition, new Qubit 4 includes a built-in reagent calculator to easily determine the amount of dye and buffer required to prepare your samples and standards (Figure 2).

Figure 1. Qubit 4 Fluorometer workflow.

Figure 2. Integrated reagent calculator. Enter the number of samples and standards needed to calculate the amount of dye and buffer.

Assays for use with the Qubit Fluorometer

The Qubit assays for use with the Qubit Fluorometer are all performed using the same general protocol, which utilizes a simple mix-and-read format, with incubation times of only 2 minutes required for DNA and RNA assays or 15 minutes for the protein assay (Figure 3). The Qubit 4 Fluorometer automatically saves your data, and you can transfer it using the USB cable or a USB drive. In addition to our core assays for dsDNA, oligos, total RNA, microRNA, and protein, Ion Sphere Particle quality can be evaluated on the Qubit 4 Fluorometer using the Ion Sphere Quality Control Kit prior to performing a sequencing run on the Ion Personal Genome Machine (PGM) Sequencer.

Sensitive, accurate biomolecule quantification

The Qubit Fluorometer utilizes fluorescent dyes that are specific to the target of interest. These fluorescent dyes emit only when bound to the target molecules, even at low concentrations (Figure 4). The Qubit 4 Fluorometer is more sensitive than UV absorbance, which measures anything absorbing at 260 nm—DNA, RNA, protein, free nucleotides, or excess salts. Moreover, UV spectrophotometry often does not have the sensitivity to accurately measure low concentrations of DNA and RNA (Figure 5). With the Qubit Fluorometer, your research is enhanced by more accurate measurements because the dyes in the Invitrogen Qubit assay kits fluoresce only when bound to the selected molecule—DNA, RNA, or protein—in your sample. This allows you to avoid repeating work due to inaccurate measurements.

Figure 4. Performance of the Qubit dsDNA HS Assay. The Invitrogen Qubit dsDNA HS Assay has a linear detection range of 0.2–100 ng and is selective for dsDNA, even in the presence of an equal mass of RNA.

Figure 5. Accuracy and precision of the Qubit Quantitation Platform. Ten replicates of lambda DNA at concentrations from 0.01 to 10 ng/μL were assayed using the Qubit dsDNA HS Assay on the Qubit Fluorometer according to the standard kit protocol. The same concentrations of DNA were measured in 10 replicates using a microvolume spectrophotometer, and results were compared for both accuracy and precision. Each bar represents the average of 10 replicates. Error bars represent the standard deviations of the 10 replicates. The concentrations indicated are the concentrations of DNA in the starting samples, before dilution in the Qubit assay tubes.

Featured video: Quantitation—Comparing Qubit fluorometer to the Nanodrop One UV/Vis absorbance

The best of both worlds

The combination of the Thermo Scientific NanoDrop One UV-Vis Spectrophotometer and the Qubit Fluorometer enables accurate, easy, and fast quantitation of biomolecules.

System specifications

Instrument dimensions

5.4 in (w) x 10 in (l) x 2.2 in (h) (13.6 cm x 25 cm x 5.5 cm)

Weight

743 g

Dynamic range

5 orders of magnitude

Processing time

≤5 seconds/sample

Light sources

Blue LED (max ~470 nm) Red LED (max ~635 nm)

Excitation filters

Blue 430–495 nm Red 600–645 nm

Emission filters

Green 510–580 nm Red 665–720 nm

Detectors

Photodiodes: measurement capability from 300–1,000 nm

Warm-up time

<35 seconds

USB drive

4 GB

Fluorometer mode

By switching to Fluorometer mode, the Qubit Fluorometer can be used as a mini-fluorometer. In Fluorometer mode, rather than performing an assay calibration and calculating results based on an algorithm, the instrument generates and displays raw fluorescence (RFU) values for each sample.

Fluorometer mode allows you to manually select the excitation source: blue LED or red LED. If blue excitation is chosen, the instrument reads the fluorescence in both the green and far red emission channels; if red excitation is chosen, emission is read in the far-red channel only.

Data gathered in Fluorometer mode may be used to design your own assay. See MyQubit for more information.

Step 4. Read tube For Blue excitation, the Qubit Fluorometer displays both the green emission and the far-red emission of your sample. For Red excitation, you will see the far-red emission of your sample. Remove the tube and press Read tube to read the next sample.

MyQubit—Envision and create new assays for the Qubit 4 Fluorometer

The Qubit 4 Fluorometer is compatible with the MyQubit assay design tool. MyQubit allows you to create new assays for the Qubit 4 Fluorometer in minutes. Simply enter your assay parameters into the online tool, and then save and upload the .qbt file to the Qubit 4 Fluorometer.

Fluorometer mode

By switching to Fluorometer mode, the Qubit Fluorometer can be used as a mini-fluorometer. In Fluorometer mode, rather than performing an assay calibration and calculating results based on an algorithm, the instrument generates and displays raw fluorescence (RFU) values for each sample.

Fluorometer mode allows you to manually select the excitation source: blue LED or red LED. If blue excitation is chosen, the instrument reads the fluorescence in both the green and far red emission channels; if red excitation is chosen, emission is read in the far-red channel only.

Data gathered in Fluorometer mode may be used to design your own assay. See MyQubit for more information.

Step 4. Read tube For Blue excitation, the Qubit Fluorometer displays both the green emission and the far-red emission of your sample. For Red excitation, you will see the far-red emission of your sample. Remove the tube and press Read tube to read the next sample.

MyQubit—Envision and create new assays for the Qubit 4 Fluorometer

The Qubit 4 Fluorometer is compatible with the MyQubit assay design tool. MyQubit allows you to create new assays for the Qubit 4 Fluorometer in minutes. Simply enter your assay parameters into the online tool, and then save and upload the .qbt file to the Qubit 4 Fluorometer.